U.S. patent application number 09/964135 was filed with the patent office on 2003-03-27 for computer-assisted-design of piping swing-joint intersections.
Invention is credited to Hoeft, David Henry.
Application Number | 20030061011 09/964135 |
Document ID | / |
Family ID | 25508171 |
Filed Date | 2003-03-27 |
United States Patent
Application |
20030061011 |
Kind Code |
A1 |
Hoeft, David Henry |
March 27, 2003 |
Computer-assisted-design of piping swing-joint intersections
Abstract
A design assistance method and apparatus is provided for
creating swing joint layout objects for interconnection among
layout objects for use in a computer assisted design apparatus, the
apparatus including an input means, a display device, a storage and
a processor connected to the input means, the display including
image data representative of layout objects and the storage
including layout object data and layout object image data.
Inventors: |
Hoeft, David Henry;
(Highlands Ranch, CO) |
Correspondence
Address: |
Scott L. Terrell
Scott L. Terrell, P.C.
Ste. 225
1746 Cole Blvd.
Golden
CO
80401
US
|
Family ID: |
25508171 |
Appl. No.: |
09/964135 |
Filed: |
September 27, 2001 |
Current U.S.
Class: |
703/1 |
Current CPC
Class: |
G06T 19/20 20130101;
G06T 17/10 20130101; G06F 2113/14 20200101; G06T 2219/2004
20130101; G06F 30/18 20200101 |
Class at
Publication: |
703/1 |
International
Class: |
G06F 017/50 |
Claims
I claim:
1. A design assistance method for creating swing joint layout
objects for interconnection among layout objects for use in a
computer assisted design apparatus, the apparatus including an
input means, a display device, a storage and a processor connected
to the input means, the display including image data representative
of layout objects and the storage including layout object data and
layout object image data, comprising the steps of: (a) retrieving
layout object data of layout objects specified by the input means
and image data graphically representing the specified pipe layout
objects from the storage; (b) collecting layout object data of the
layout objects and the specified layout objects; (c) retrieving
design reference data which establishes a maximum jog-over
distance; (d) finding a first end of a source pipe layout object
wherein the first end is not terminating in a layout object using
the layout object data and the specified layout object data; (e)
finding a target pipe layout object end having a least distance
within the maximum jog-over distance relative to the first end
using the specified layout object data and the maximum jog-over
distance; (f) generating at least one swing-joint layout object
interconnecting the first end and the target pipe layout object
end; (g) storing layout object data representing the swing joint
layout object and adding the stored layout object data to the
collection; and (h) displaying image data representing the layout
object data of the collection.
2. The design assisting method according to claim 1 wherein the
layout object data further comprises functional data and
selectively removing layout object data from the collection using
the functional data.
3. The design assisting method according to claim 1 wherein finding
a target pipe layout object end further comprises evaluating the
first end for 180.degree. rotation in order to attain the least
distance.
4. The design assisting method according to claim 1 further
comprising consolidating the layout object data in the design
layout.
5. A design assisting apparatus for interactively creating
swing-joint layout objects on a display device, comprising: (a)
means for determining a swing joint layout object relative to
specified layout objects using a least swing distance within a
maximum jog-over distance, the specified layout objects selected
using an input means and comprising a source pipe layout object end
a target pipe layout object end; and (b) means for graphically
displaying on the display device the determined swing joint layout
objects relative to the specified objects.
6. A design assisting apparatus for creating swing-joint layout
objects interconnecting a plurality of specified layout objects
among layout objects displayed on a display device, comprising: (a)
an input means for specifying a pipe layout object image and a
maximum jog-over distance; (b) a first memory for storing layout
object image data; (c) a second memory for storing layout object
data; (d) a third memory for storing a process sequence wherein
said process sequence retrieves layout object data of layout
objects specified by the input means and image data graphically
representing the specified pipe layout objects from a storage,
collects layout object data of the layout objects and the specified
layout objects, and establishes a maximum jog-over distance for
swing joint interconnection between the specified layout objects;
(e) a processing means for finding a first end of a source pipe
layout object wherein the first end is not terminating in a layout
object using the layout object data and the specified layout object
data, finding a target pipe layout object end having a least
distance within the maximum jog-over distance relative to the first
end using the specified layout object data and the maximum jog-over
distance, generating at least one swing-joint layout object
interconnecting the first end and the target pipe layout object
end, storing layout object data representing the swing joint layout
object, and adding the stored layout object data to the collection;
and (h) a display device for displaying image data representing the
layout object data of the collection.
7. The design assisting apparatus according to claim 6 wherein the
layout object data further includes functional data and the process
sequence further comprises selectively removing layout object data
from the collection using the layout object functional data
8. The design assisting apparatus according to claim 6 wherein the
process sequence further comprises evaluating the first end for
180.degree. rotation in order to attain the least distance.
9. The design assisting apparatus according to claim 6 wherein the
process sequence further comprises consolidating the layout object
data.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] Not Applicable.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a method and apparatus for
computer-assisted-design ("CAD") of piping systems. In particular,
the invention relates to a CAD method and apparatus suitable for
creating swing-joint intersections between sections of piping in a
three-dimensional drawing.
[0004] 2. Description of the Related Art
[0005] The design of a layout area consisting of layout piping
objects, such as water delivery pipes for use in a fire sprinkler
system, requires the interconnection of the pipes arranged in three
dimensional space. When two pipes must interconnect it is desirable
to design the layout so that the connections may be formed at
90.degree. angles rather than bends. This design enables the pipes
to be assembled, in an actual construction, using standard "elbow"
fittings which typically include a 90.degree. change in direction.
By using two 90.degree. degree changes of direction, a pipe can
jog-over to interconnect with another pipe. This connection is a
"swing-joint".
[0006] In conventional systems for the CAD layout of piping
systems, swing-joints are manually determined by the designer while
he/she watches the design drawings and data. The decision as to
which layout objects should be relocated, in what sequence, and by
what amount of movement is left to the operator. As a result, it
takes a great deal of the designer's time and effort to create
swing-joint intersections in the design layout. Swing-joint
intersections are particularly difficult to calculate manually
because pipe layout object segments must be modified to arrive at
that point, in three dimensional space, where the pipes can be
interconnected with elbow fittings. Moreover, after modification of
the pipe layout object segments, it is time consuming to
consolidate the modified arrangement of segments into a design
layout which is efficient for application in an actual
construction.
[0007] Computer assisted design systems which automate some of the
decision making processes are also well known. For example,
Mitsuta, et al., U.S. Pat. No. 4,831,546, discloses a design system
for routing piping (in the layout planning of building
installations a method of optimally determining the optimal piping
route relative to interfering objects by entering data of
installation layout, layout objects, and data of design reference)
and, Yoshida et al., U.S. Pat. No. 4,992,953, discloses a computer
assisted design method and apparatus for finding and displaying a
graphic pattern of a liquid stay area (layout object data relating
to the layout object specified by an input device and a liquid
discharger arrangement rule). However, with these design systems,
changes in direction are simply located where the piping bends to
overcome the interfering or arranged objects in the design
layout.
[0008] Thus, what is needed is a method and apparatus which is
suitable for creating swing-joint intersections between sections of
piping in a three-dimensional CAD drawing. There also exists a need
for a system which enables the designer to rapidly create
swing-joint intersections, in a three dimensional CAD piping design
layout, among user specified layout objects depicted in the design
display. A further need exists for an automated method and
apparatus which is useful to mathematically determine the optimal
locations for turning the piping in order to create the swing-joint
intersections in three dimensional space and to modify and
consolidate the piping layout object segments for use in an actual
construction. The disclosed invention satisfies these needs.
SUMMARY OF THE INVENTION
[0009] A primary object of this invention is to provide a method
and apparatus for assisting layout design which readily pinpoints
locations for the creation of swing-joint layout objects for
intersection among a plurality of layout objects.
[0010] It is another object of the present invention to provide a
design assistance method and apparatus which is useful to rapidly
create swing-joint intersections among specified piping and fitting
layout objects depicted on a display device.
[0011] It is yet another object of the present invention to provide
a design assistance method and apparatus which can precisely create
swing-joint intersections among a plurality of design objects for
assembly in an actual construction using 90.degree. elbow
fittings.
[0012] It is a further object of the invention to provide a design
assistance method and apparatus which can precisely consolidate
design layout objects, representative of pipes and fittings, after
modification the design to include swing-joint layout objects.
[0013] These and other objects of the present invention will become
apparent throughout the description of the invention which now
follows.
[0014] Briefly, the invention provides a design assistance method
for creating swing joint layout objects for interconnection among
layout objects for use in a computer assisted design apparatus, the
apparatus including an input means, a display device, a storage and
a processor connected to the input means, the display including
image data representative of layout objects and the storage
including layout object data and layout object image data, which
includes the steps of: retrieving layout object data of layout
objects specified by the input means and image data graphically
representing the specified pipe layout objects from the storage;
collecting layout object data of the layout objects and the
specified layout objects; retrieving design reference data which
establishes a maximum jog-over distance, finding a first end of a
source pipe layout object wherein the first end is not terminating
in a layout object using the layout object data and the specified
layout object data; finding a target pipe layout object end having
a least distance within the maximum jog-over distance relative to
the first end using the specified layout object data and the
maximum jog-over distance; generating at least one swing-joint
layout object interconnecting the first end and the target pipe
layout object end; storing layout object data representing the
swing joint layout object and adding the stored layout object data
to the collection; and displaying image data representing the
layout object data of the collection.
[0015] Unless specifically defined otherwise, all technical or
scientific terms used herein have the same meaning as commonly
understood by one of ordinary skill in the art to which this
invention belongs. Although any methods and materials similar or
equivalent to those described herein can be used in the practice or
testing of the present invention, the preferred methods and
materials are now described.
[0016] "Layout objects" means pipe and fitting elements in an
object data oriented computer-aided-design which are representative
of actual pipes and fittings. Pipes objects exist in the drawing as
segments and the segments are interconnected using layout objects
which represent actual pipe fittings.
[0017] "Swing-joint" means pipe ends interconnected using flange,
screw, bell and spigot, weld, or solder, at 90.degree. or
45.degree., turned up, or turned down, and further include pipe
ends interconnected at 180.degree. using a joint fitting.
[0018] "Jog-Over" means the maximum distance condition that two
pipes may be laterally separated for interconnection by a
swing-joint layout object.
[0019] "Swing distance" is the distance between two separated pipes
for interconnection using a swing-joint.
DESCRIPTION OF THE DRAWINGS
[0020] The present invention is illustrated by way of example and
not limitation in the accompanying figures in which like reference
numerals indicate similar elements and in which:
[0021] FIG. 1 is a block diagram of the layout design assisting
system embodying the present invention.
[0022] FIGS. 2-8 are a flow charts explaining the operational
sequence of the layout design assisting system shown in FIG. 1.
[0023] FIG. 9 is a diagram showing an example of a display on the
display unit of a sprinkler system pipe layout design in a case
where the source and target pipes for swing-joint interconnection
exists in a parallel relationship (90) and where the pipes are in a
parallel and collinear relationship (60).
[0024] FIG. 10 is a diagram showing an example of a display on the
display unit of a sprinkler system pipe layout design in a case
where source sprinkler pipes can be reversed to form swing-joint
intersections with target pipes.
[0025] FIG. 11 is an illustration diagram showing a classic example
of a display on a display unit of a sprinkler system pipe layout
design in a case where the non-parallel sprinkler pipes are to be
hung under a pitched roof and exist is the display in a
non-parallel relationship.
DETAILED DESCRIPTION OF THE INVENTION
[0026] The computer architecture and associated hardware for
designing swing-joint interconnections in a CAD system of piping is
well known, and many suitable computer and hardware combinations
may be programmed to complete the system according to the present
invention. Typical examples of the computer architecture and
hardware are described in the foregoing patents which are
incorporated by reference herein.
[0027] Turning now to the drawing figures wherein like numerals
represent like elements there is shown in FIG. 1 a block diagram of
the layout design assisting system embodying the present invention.
The layout design assisting system includes a display device 1, a
graphic display controller 2, a graphic data memory 3, an input
device such as a keyboard and mouse pointer 4, an arithmetic
processing unit 5, piping layout object data memory 6, a
swing-joint design reference data memory 7, including a maximum
jog-over distance and a swing distance, and a layout area graphic
data memory 8. The arithmetic processing unit 5 consists of a
arithmetic operator, an operation sequence memory, an input port, a
graphic data input port, a design object graphic data search signal
output port, and a design reference data search signal output port.
Graphic data, to be displayed, is produced in the arithmetic
processing unit and stored in the graphic image data memory.
[0028] The graphic display controller 2 retrieves graphic data from
the graphic data memory 3 and displays it on the display unit 1.
The object data memory 6 stores data related to layout objects
(pipe and fitting elements). Stored layout object data includes
data of a specified pipe elements for swing-joint interconnection.
Layout object data for piping includes the pipe diameter and
coordinates (x, y, z) of the pipe ends, and the location for each
pipe layout object in the drawing display 1. Layout object data
may, but need not, also include functional data representative a
layout objects function in the design. The design reference data
memory 7 stores design reference data which includes a maximum
jog-over distance specified by the user through the keyboard input
device 4.
[0029] The present invention is implemented in a CAD program
structure of a computer. The logical concept for describing
components of the computer program are known as objects. An object
is used to define the properties and interfaces of a system
component. The computer program is an assembly of one or more
objects. This object structure helps to clearly define and
encapsulate the components of the computer program. The program
uses "Object Oriented Programming", an industry standard practice,
well know in the art, for program definition, design, and
development. The objects herein, are implemented in C++ program
code as classes. A class is a C++ programming language data
structure that exists to implement the logical concept of an
object. A class is used to encapsulate the data/properties and
methods/interfaces of an object into a single data structure.
[0030] Three basic foundation structure programs are initially
stored into the computer memory to implement the design of
swing-joint intersections among pipe layout objects for display in
the drawing according to the present invention. First, Microsoft
Foundation Program Structure is a program based upon the Microsoft
standard Multi-Document Interface (MDI). This program model is
built upon a base consisting of four fundamental objects:
Application, Frame, Document, and View. The Application, sold under
the trademark, MICROSOFT FOUNDATION CLASS LIBRARIES (MFC), provides
these utilitarian objects and represents a program itself. It is
through the Application object that the process is initiated and
all other objects that comprise the invention come into existence.
The application creates the Frame, Document, and View objects. The
Frame object represents the frame window of the Application that
becomes visible to the user and acts as the manager for subsequent
user interface objects, such as other windows. The Frame object
encapsulates the internal data structures used by the operating
system, sold under the trademark MICROSOFT WINDOWS.RTM., to create
and maintain an application's parent window. The Document object
represents an instance of the user's data and is stored to disk for
later retrieval. Many Document objects can exist for each instance
of the program, enabling the program to open several documents
simultaneously. The View object represents a view into the data of
a Document object. The View object provides the user with a visual
interface to the Document. The View object encapsulates the
internal data structures used by the MICROSOFT WINDOWS.RTM.
operating system to create and maintain an application's child
window. Many View objects can exist for each Document object,
enabling the program to display several different views of the same
document simultaneously.
[0031] The second foundation program is a CAD foundation sold under
the trademark SYMMETRICA.RTM. for the piping system design
software. This software comprises a set of programming objects that
expands upon the MFC program structure. It adds capability to the
MFC Application, Frame, Document, and View objects, enabling them
to offer the fundamental behavior and interfaces of a CAD program.
Many essential objects provided by this program support the needs
of a CAD program. Derived from MICROSOFT MFC Objects, are an
Application object necessary to support the CAD program, and a
Frame object which establishes the parent window framework required
to support the CAD program objects. A Document object is used to
provide all the capability required to encapsulate CAD drawing
data, which includes drawing elements and user settings appropriate
to each drawing. A View object provides a visual interface to the
document object. This View object provides the three dimensions
view rotation and scaling properties, enabling the user to view the
document's data from any arbitrary three dimension, view rotation,
and magnification. It also provides for requesting three
dimensional Cartesian coordinate (x, y, z) point input from the
user. Input is provided by the system pointing device (mouse), the
keyboard, or both. Also provided is a base class object of all CAD
drawing elements, such as lines, arcs, circles, etc., that can be
managed by the Document object and displayed by the View object.
This object defines the interface to the CAD drawing elements that
all derived classes inherit through standard C++ mechanisms. This
standard interface enables the definition of the new kinds of
elements for the CAD drawing, such as a pipe layout object derived
from a line segment. The CAD foundation program further acts as the
foundation program for the piping swing-joint interconnection
design program.
[0032] The third foundation program is the program sold under the
trademark OBJECT DBX.RTM.. This program is a collection of objects
for reading, writing, and viewing DWG and DXF drawing files. This
file format is well known in the art, the industry standard for the
exchange of drawing files, and is used in the preferred embodiment
of the invention. Using OBJECT DBX.RTM. objects, the above CAD
foundation has the capability to read, write, and view DWG and DXF
drawing files. This capability has been implemented in the CAD
program Document and View objects. DWG and DXF drawing files can be
read/appended to a CAD drawing, of the above program, and the CAD
drawings may be stored on a data storage medium as DWG and DXF
drawing files. Additionally, DWG and DXF drawing files can be
selected as a backdrop to the current CAD drawing. This method
enables the CAD program to make full use of the programs high-speed
display objects to view DWG and DXF drawings. When the display must
be refreshed, the background drawing is displayed first,
immediately followed by the elements of the CAD drawing.
[0033] Turning now to the drawing figures there is shown in FIG. 9,
a diagram showing an illustration of a display on the display unit
of a sprinkler system pipe layout design 10 in a case where the
source and target pipes for swing-joint interconnection exist in a
parallel relationship (90) and where the pipes are in a parallel
and collinear relationship (60). The layout drawing may be created
by storing in a first memory means a drawing view 10 of a piping
system, the drawing comprised of a plurality of changeable
interengageable pipe layout objects, such as water delivery pipes
20 for a fire sprinkler system, representational of an actual
construction, for selective assembly together. The elements have
distinctive properties that enable the three-dimensional pipe
diameter and the coordinates (x, y, z) for location of each pipe
end 30 for each pipe layout object 20 in the drawing. The drawing
is displayed on the display device 1. Optimally, for each pipe
layout object 20 the display further exposes a property dialog
window for identification of each pipe layout object's 20
application in a system of piping, e.g., whether the pipe is a
branch line, Cross Main, Riser Nipple, Arm Over, Sprig. Drop,
etc.
[0034] Referring now to FIG. 2, after creating 310 and displaying
the drawing view 10, having a new layout of pipe layout objects or
by loading an existing layout of pipe layout objects, the designer
selects two or more pipe layout objects ("specified layout
objects") 320 for swing-joint interconnection using the input
device 4, such as a mouse pointer, keyboard or digitizer. For
example, with reference to again FIG. 9, the designer would select
pipe layout objects 62, 64, 92, and 94 for swing-joint
interconnection.
[0035] The designer then retrieves or inputs design reference data
which defines a maximum jog-over distance 330 for the swing-joint
connections. The longest jog-over distance condition provides
control over the creation of swing-joints between pipe layout
objects in the drawing.
[0036] The computer then compiles a collection 340, or list, of all
pipe and fitting layout objects already existing in the drawing of
the system (the "existing layout objects" herein). In one
embodiment of the invention, auxiliary pipe layout objects may, but
need not, be selectively removed from the collection based upon
their function in the system. For example, pipe layout objects
which are assigned, through their respective properties dialog
windows, to be a Riser Nipple, Arm Over, Sprig, or Drop would be
removed from the collection 340. This enables swing-joints (at 90
and 60 in FIG. 10) to be created between pipes 20 that often
terminate in an auxiliary pipe. The following logic prevents the
creation of a swing-joint at such pipes had they not been removed
from the collection.
[0037] Each end 30 of each specified pipe is examined 3 50, in
turn, to find a suitable target pipe, among the specified layout
objects, at which to create a swing-joint. If a suitable target
pipe is found, a swing-joint is created. As each specified pipe end
is processed 350, this description refers to the specified pipe
whose end is being processed, relative to a candidate target pipe,
as the "source pipe".
[0038] Turning now to FIG. 3, if the source pipe end already
terminate, such as by a fitting, at an existing pipe end 400, the
pipe end is ignored and processing continues to the next source
pipe end 350. The next pipe end may be the opposite end of the
current source pipe, an end of the next pipe among the specified
pipes, or there may be no more specified pipe ends which remain to
be processed 370.
[0039] The best suitable candidate among the specified pipes is
determined to be the swing target 420. This step is performed
iteratively upon every potential candidate. First, the swing
distance is calculated 430. For example, as shown in FIG. 9, for
pipe layout objects 62 and 64, existing in a parallel and collinear
relationship 60, the swing distance 66 equals the distance from the
source pipe 62 end 30, being processed, to the closest end 30 of
the candidate pipe 64. At 90, for parallel pipes existing in a
non-collinear relationship the swing distance 96 is calculated as
the distance between dotted lines 98 which are computed rays
extending lengthwise through the pipes 94 and 92 ends 30.
[0040] As shown in FIG. 11, for source 72 and target pipes 74,
existing in a non-parallel and non-collinear-relationship, a dotted
line 75 is calculated that intersects extensions of both dotted
lines formed by the pipes 74, 72 such that the intersection with
each line forms a 90.degree. angle, at P1 to P4. There will be only
one such line 75. The swing distance is the distance between the
two intersection points P1 to P2 and P3 to P4. If the swing
distance, such as P1 to P6 is greater than the maximum jog-over
distance, set by the user, the candidate 74 is ignored and
processing continues to the next potential candidate 74.
[0041] Referring once again to FIG. 3, the point to which the pipe
end 30 must be extended is checked to determine if it requires a
reversal of the direction of the pipe end 450. For example, in FIG.
10, if the swing points 76 are not on a ray A projected from the
source pipes 72 ends 30, then a reverse of the pipes 72 end's 30
direction is required to reach the swing points 76. The source
pipes 72 are tested to see whether reversal is possible under
conditions that: (1) the source pipes 72 and the candidates 74 must
not be parallel; and (2) there must already be pipes 77 connected
to the ends 31 opposite source pipes 72 ends 30. If reversal of the
source pipe's 72 direction is required but is not possible, the
candidate 74 is ignored and processing continues to the next
potential candidate. The candidate 74 that results in the shortest
swing distance 460 is determined to be the swing target and the
pipe 72 is reversed and connected consistent with the dashed line
segments 73. Where the swing target 74 has been found, and the
source pipe 72 direction has not been reversed, the computer will
add up to three new pipe segments 73 to the existing pipes list
(dashed lines in circle 110, FIG. 11).
[0042] Referring now to FIG. 9 and FIGS. 5 to 8 the operational
steps for the addition of the new pipe segments to the existing
pipe list are shown. In FIG. 9, where the source pipe 62 and
candidate 64 are in the parallel collinear relationship 60, the
closest end 30 of the swing target 64 to the pipe 62 end is
determined 700, and the closest end 66 of the swing target 64 is
then extended (dashed line) to the source pipe 62 end 30 where a
straight fitting is created (step 710).
[0043] For parallel pipes, 92, 94, (step 550) an intersection point
is calculated as that point 91 at which line 93, extends
perpendicular to vectors 98, passing through both pipe lines 92 and
94, intersects the target pipe 94 end 30. A pipe segment 95 is
created from the pipe end 30 to the intersection point 91 on the
target pipe line 94, and a segment is created from the closest end
30 of the target pipe 94 to the intersection point 91.
[0044] Lastly, as exemplified in FIG. 11 at circle 110, for
non-parallel pipes 72, 74, having a non-coplanar relationship in
the existing layout drawing, a line 75 is calculated which
intersects vectors passing through both lines formed by source
pipes 72 and candidates 74 such that the intersections, at points
P1 to P2, and P3 to P4 with each vector forms a 90 degree angle.
The ends 30 of pipes 72 are extended (dashed line) to the
intersection points P2 and P3 along the source pipes 72 calculated
line (dotted). A pipe segment 77 is created between the two
intersection points unless the two points P1 and P2 are at the same
location. The closest end 30 of the target pipes 74 is extended to
the intersection points P1 and P4 along the target pipe line.
[0045] The non-parallel pipes 72 and 74 may also be in a co-planar
relationship as illustrated at circle 120. The intersection point
P5 may not be at a point where extensions of pipe segments 72 and
74 meet at 90 degrees. In this instance, the intersecting line is
the point P5 and with only one intersecting point P5, two segments
(dashed lines) are created.
[0046] As shown in FIGS. 5 and 10, the addition of the new pipes to
the list 640 is slightly different where the source pipe's 72
direction opposite ray A must be reversed. The mutual intersect
line 75 is first calculated 600. The swing-joint is constructed 610
from the opposite end 31 of the source pipe 72, rather than from
the pipe end 30 being processed. The source pipe 72 is deleted 640
after the swing-joint is created 630. The source pipe 72 is removed
from the list of existing pipes 650, and from the list of specified
pipes. In FIG. 4, for each of the above examples, the newly created
pipes 73 are then added 580 to the collection of existing
pipes.
[0047] Referring once again to FIG. 2, the newly created pipes
which have been added to the collection of existing pipes are added
for analysis relative to the next specified pipe end to be
processed 350. After all of the specified pipes have been processed
370, the pipe segments are consolidated together 380 where
possible, including all pipes that were identified by the CAD
operator and pipes that were added to create swing-joints. The
consolidations results in one of the pipe segments being removed
from the CAD drawing. The remaining pipe segment is extended to
fill the space vacated by the pipe segment which has been
deleted.
[0048] While the present invention has been illustrated and
described with reference to particular structures and methods of
fabrication, it will be apparent that other changes and
modifications can be made therein within the scope of the present
invention as defined by the appended claims.
* * * * *